THE RESPIRATION OF ASCARIS LUMBRICOIDES EGGS

The rate of oxygen consumption of developing ascaris eggs decreased rapidly to a minimum after 1.5 days, and thereafter increased to a maximum at 10 days, when the embryos were vermiform. During the 10–20 day period, when the embryo matures and molts once in the egg, the respiration decreased steadily, and continued to decrease more slowly until at 140 days the rate was scarcely measurable. Nevertheless, the eggs remained viable and hatched readily in the mouse gut. Cytochrome c and cytochrome oxidase could not be detected by direct assay or isolation. However, the high sensitivity of the respiration to carbon monoxide (in the dark), to cyanide, and to azide, and the low sensitivity to carbon monoxide (in the light) and to decreasing partial pressures of oxygen, indicated that oxidases such as the flavoproteins, phenolases, and peroxidases were unlikely respiratory catalysts, and that cytochrome oxidase, or a similar and hitherto undescribed enzyme, was the major component of the terminal respiratory enzyme system.

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The Respiratory Function of the Haemoglobin of the Earthworm

Journal of Experimental Biology ◽

10.1242/jeb.18.3.266 ◽

1942 ◽

Vol 18 (3) ◽

pp. 266-277

Author(s):

M. L. JOHNSON

Keyword(s):

Carbon Monoxide ◽

Oxygen Consumption ◽

Oxygen Pressure ◽

Respiratory Function ◽

Respiratory Enzymes ◽

Partial Pressures ◽

Rate Of Oxygen Consumption

The oxygen consumption of earthworms (Lumbricus herculeus Savigny) has been measured at 10°C., in the dark, in atmospheres containing 20, 10, 5, 2.5 and 1% of oxygen (i.e. at partial pressures of oxygen of about 152, 76, 38, 19 and 8 mm. mercury), with and without the addition of enough carbon monoxide to saturate the haemoglobin of the blood. In the absence of carbon monoxide the rate of oxygen consumption was significantly the same at 152 and 76 mm.; below 76 mm. it fell sharply. The rate of oxygen consumption of carbon monoxide-treated worms was significantly lower than that of normal worms at oxygen pressures of 152, 76, 38 and 19 mm. but not at 8 mm. The respiration of slices of earthworm has been measured in atmospheres containing 20% of oxygen, and 20% of oxygen together with 20% of carbon monoxide. The rate of respiration in the presence of carbon monoxide was 110% of that in its absence. It is concluded that the lowering of the rate of respiration of whole worms caused by carbon monoxide was not due to inhibition of respiratory enzymes, but to its effect on haemoglobin. Haemoglobin therefore transports oxygen at atmospheric as well as at lower partial pressures of oxygen. Less oxygen was carried by haemoglobin at 19 mm. than at 38 mm. It is deduced that the loading pressure of earthworm haemoglobin is higher than 19 mm. The haemoglobin, of the blood was responsible for supplying about 23% of the respired oxygen when the oxygen pressure was at 152 mm., 35% at 76 mm., 40% at 38 mm.; and 22% at 19 mm. of oxygen.

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Oxygen sensitivity in the insect Prodenia eridania

American Journal of Physiology-Legacy Content ◽

10.1152/ajplegacy.1960.198.2.441 ◽

1960 ◽

Vol 198 (2) ◽

pp. 441-444 ◽

Cited By ~ 6

Author(s):

Arnold M. Clark ◽

V. J. Cristofalo

Keyword(s):

Carbon Monoxide ◽

Oxygen Consumption ◽

Metabolic Rate ◽

Adult Stage ◽

Oxygen Sensitivity ◽

Rate Of Oxygen Consumption ◽

Injurious Effects

Both the larval and pupal stages of prodenia eridania are injured by oxygen at increased pressures. The injury is manifested by a reduction in the rate of oxygen consumption, muscular paralysis and failure to develop to the adult stage. In the pupae these effects appear together as a syndrome. Pupae are much more sensitive than larvae. At least 75 psi of oxygen is necessary for injury to larvae while only 45 psi is required to produce injury in the pupae. Injured pupae respire at a rate 2%–5% of the controls while the injured larvae consume oxygen at 60% of the control rate. In attempts to modify this sensitivity by pretreatment with agents which reduce the metabolic rate, it was found that pupae kept at –10°C for 30 minutes before treatment or kept in carbon monoxide or nitrogen for 30 minutes prior to treatment showed none of the injurious effects of oxygen.

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Nitric oxide regulation of mitochondrial oxygen consumption II: molecular mechanism and tissue physiology

AJP Cell Physiology ◽

10.1152/ajpcell.00310.2006 ◽

2007 ◽

Vol 292 (6) ◽

pp. C1993-C2003 ◽

Cited By ~ 110

Author(s):

Chris E. Cooper ◽

Cecilia Giulivi

Keyword(s):

Nitric Oxide ◽

Oxygen Consumption ◽

Cytochrome C ◽

Cytochrome Oxidase ◽

Molecular Mechanism ◽

Guanylate Cyclase ◽

Redox State ◽

Physiological Role ◽

Metabolic Effects ◽

Whole Body

Nitric oxide (NO) is an intercellular signaling molecule; among its many and varied roles are the control of blood flow and blood pressure via activation of the heme enzyme, soluble guanylate cyclase. A growing body of evidence suggests that an additional target for NO is the mitochondrial oxygen-consuming heme/copper enzyme, cytochrome c oxidase. This review describes the molecular mechanism of this interaction and the consequences for its likely physiological role. The oxygen reactive site in cytochrome oxidase contains both heme iron ( a3) and copper (CuB) centers. NO inhibits cytochrome oxidase in both an oxygen-competitive (at heme a3) and oxygen-independent (at CuB) manner. Before inhibition of oxygen consumption, changes can be observed in enzyme and substrate (cytochrome c) redox state. Physiological consequences can be mediated either by direct “metabolic” effects on oxygen consumption or via indirect “signaling” effects via mitochondrial redox state changes and free radical production. The detailed kinetics suggest, but do not prove, that cytochrome oxidase can be a target for NO even under circumstances when guanylate cyclase, its primary high affinity target, is not fully activated. In vivo organ and whole body measures of NO synthase inhibition suggest a possible role for NO inhibition of cytochrome oxidase. However, a detailed mapping of NO and oxygen levels, combined with direct measures of cytochrome oxidase/NO binding, in physiology is still awaited.

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Reduction of Cytochrome c by Tetrathionate in the Presence of Tetrathionate Hydrolase Purified from Sulfur-Grown Acidithiobacillus Ferrooxidans ATCC 23270

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.71-73.243 ◽

2009 ◽

Vol 71-73 ◽

pp. 243-246

Author(s):

Taher M. Taha ◽

Fumiaki Takeuchi ◽

Tsuyoshi Sugio

Keyword(s):

Cytochrome C ◽

Cytochrome Oxidase ◽

Acidithiobacillus Ferrooxidans ◽

Oxidase Activity ◽

Elemental Sulfur ◽

Enzyme System ◽

Size Exclusion ◽

Ammonium Sulfate Precipitation ◽

Interesting Phenomenon ◽

Oxidase Enzyme

It is mysterious that, when A. ferrooxidans ATCC 23270 cells grow on elemental sulfur, they have high iron oxidase activity comparable to that of iron-grown cells as well as high activities of sulfide:ferric ion oxidoreductase (SFORase) and tetrathionate hydrolase. To clarify this interesting phenomenon, cytochrome c and tetrathionate hydrolase were purified from sulfur-grown A. ferrooxidans cells using ammonium sulfate precipitation, Phenyl column chromatography, and SuperdexTM 75 and Sephadex G-100 size exclusion column chromatographies. The purified cytochrome c was reduced by tetrathionate in the presence of purified tetrathionate hydrolase, but not in the absence of the enzyme. When the partially purified cytochrome c fraction containing aa3-type cytochrome oxidase was used, both cytochrome c and aa3-type cytochrome oxidase were reduced by tetrathionate in the presence of purified tetrathionate hydrolase. These results indicate that tetrathionate in the presence of tetrathionate hydrolase can reduce iron oxidase enzyme system containing cytochrome c and aa3-type cytochrome oxidase as tetrathionate hydrolase decomposes tetrathionate to produce thiosulfate, elemental sulfur, and sulfate; and the formed thiosulfate can chemically reduce cytochrome c and Fe3+.

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RESPIRATION OF FISHES WITH SPECIAL EMPHASIS ON STANDARD OXYGEN CONSUMPTION: III. INFLUENCE OF OXYGEN

Canadian Journal of Zoology ◽

10.1139/z64-033 ◽

1964 ◽

Vol 42 (3) ◽

pp. 355-366 ◽

Cited By ~ 76

Author(s):

F. W. H. Beamish

Keyword(s):

Oxygen Consumption ◽

Oxygen Uptake ◽

Partial Pressure ◽

Brook Trout ◽

Low Oxygen ◽

Low Level ◽

Standard Metabolism ◽

Partial Pressures ◽

Rate Of Oxygen Consumption ◽

Standard Rate

Standard oxygen consumption was determined in relation to various partial pressures of oxygen for eastern brook trout at 10° and 15 °C, and for carp and goldfish at 10° and 20 °C. Two conditions of oxygen acclimation were compared. In one case acclimation was to air saturation while in the other acclimation was to each of the partial pressures of oxygen applied.Down to a partial pressure of oxygen of approximately 80 mm Hg, standard oxygen uptake remained approximately constant, and further, the rates for the two differently acclimated groups were about equal. Below 80 mm Hg the standard rate first increased to a maximum and then, with a further reduction in the partial pressure, decreased. Below 80 mm Hg the standard rate of oxygen consumption was in all cases less for the fish acclimated to the low level of oxygen than for those acclimated to air saturation.Comparison of standard and active values suggests that the increase in standard rate of oxygen uptake in response to low oxygen does not reach the active level as suggested earlier by Fry (1947). The suggestion is made that a fraction of standard metabolism is derived anaerobically in low levels of oxygen. Further, it appears that acclimation to a low level of oxygen enhances the anaerobic fraction of standard metabolism.

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ENZYME INHIBITION BY DERIVATIVES OF PHENOTHIAZINE AND OF SULPHANILAMIDE

Canadian Journal of Research ◽

10.1139/cjr40b-043 ◽

1940 ◽

Vol 18b (11) ◽

pp. 345-350 ◽

Cited By ~ 12

Author(s):

H. B. Collier

Keyword(s):

Cytochrome C ◽

Cytochrome Oxidase ◽

Enzyme Inhibition ◽

Ascaris Lumbricoides ◽

Inhibitory Activity ◽

Spectroscopic Observation ◽

Hydroxyl Group ◽

Bactericidal Action ◽

Derivatives Of

Mammalian catalase and cytochrome oxidase are strongly inhibited by the hydroxy derivatives of phenothiazine and by p-hydroxylaminobenzenesulphonamide. Phenothiazine, sulphanilamide, and sulphapyridine have little or no effect. Cytochrome-c is irreversibly reduced by the hydroxy-sulphanilamide, as indicated by spectroscopic observation. The inhibitory activity apparently depends on the presence of the hydroxyl group. The relation of these findings to the vermicidal and bactericidal action of the compounds is discussed.Phenothiazine and thionol have no effect on Ascaris lumbricoides in vitro.

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RESPIRATION OF FISHES WITH SPECIAL EMPHASIS ON STANDARD OXYGEN CONSUMPTION: IV. INFLUENCE OF CARBON DIOXIDE AND OXYGEN

Canadian Journal of Zoology ◽

10.1139/z64-083 ◽

1964 ◽

Vol 42 (5) ◽

pp. 847-856 ◽

Cited By ~ 20

Author(s):

F. W. H. Beamish

Keyword(s):

Carbon Dioxide ◽

Oxygen Consumption ◽

Partial Pressure ◽

Brook Trout ◽

Salvelinus Fontinalis ◽

Partial Pressure Of Oxygen ◽

Partial Pressures ◽

Rate Of Oxygen Consumption ◽

Standard Rate ◽

Different Levels

Oxygen consumption was determined in relation to spontaneous activity and standard metabolism estimated by extrapolating the values to zero activity, Standard oxygen consumption was determined in relation to different partial pressures of carbon dioxide and oxygen for brook trout. Salvelinus fontinalis (Mitchill), at 10 °C, and carp, Cyprinus carpio Linnaeus, at 25 °C. In general, at each partial pressure of oxygen applied, standard oxygen consumption did not change significantly over the range of partial pressures of carbon dioxide followed. The relation for brook trout operated on a level characteristic of the partial pressure of oxygen. Although the effect of different levels of oxygen was not established for carp at 25 °C, it is presumed that the relation operated also in that species in a similar way.Acclimation to the different levels of carbon dioxide and oxygen to be tested was examined and, ordinarily, found not to change significantly the standard rate of oxygen consumption.

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Seasonal Variation in the Respiratory Acclimatization of the Leech Erpobdella Testacea (sav.)

Journal of Experimental Biology ◽

10.1242/jeb.35.2.314 ◽

1958 ◽

Vol 35 (2) ◽

pp. 314-323

Author(s):

K. H. MANN

Keyword(s):

Carbon Monoxide ◽

Oxygen Consumption ◽

Seasonal Variation ◽

Mercury Electrode ◽

Saturated Water ◽

Constant Rate ◽

Dropping Mercury Electrode ◽

Previous Level ◽

Rate Of Oxygen Consumption ◽

Normal Respiration

1. In summer the leech Erpobdella testacea becomes acclimatized to a low concentration of oxygen in the water, and can maintain a constant rate of oxygen consumption down to one-third air-saturation. This acclimatization does not occur in winter. 2. The mechanism of acclimatization is such that it can operate when the leeches are resting, and when the haemoglobin has been prevented from functioning by treatment with carbon monoxide. 3. In the course of normal respiration in air-saturated water at 20° C. about 45% of the oxygen is transported to the tissues by the haemoglobin. In one-third air-saturated water about 25% is transported in this way. 4. After a meal of Tubifex the oxygen consumption increases threefold, and declines to the previous level over a period of 4 days. 5. A polarographic respirometer embodying a wide-bore dropping mercury electrode has been developed for this work. It provides on a galvanometer a constant indication of the oxygen concentration in the water which has passed over the animals.

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